If I figure out how to post pictures I'll show my Scrapbiniumtm hub extractor which was made on the car. It's a length of large bore hydraulic tubing, a pair of lugs with 8mm drilled holes, and a thick metal disc with a nut welded over a hole in the centre. The lugs were bolted two of the brake backing plate holes, shaped to fit the tubing with an angle grinder, then all 3 pieces welded together on the car. Next I unbolted the part and welded the disc to the other end. Added a long M16 bolt, and refitted the complete extractor to the car. 30 seconds later I had the hub in my hand. We had struggled with other methods for 2 hours.
The tool looks horrible, but works well. No measurements were made, it was all done by eye. The only precision part of the job was the hole in the disc; I drilled and bored it in the lathe as I didn't have a suitable drillbit, and hacking through 10mm steel with hand tools is not fun.
I do have a 3d model of the tool, that is waiting for an accurate layout of the boltholes. With that I would have a mounting ring laser cut in 6mm steel, face the ends of the tubing in the lathe, make the disc a stepped fit into the end, and TIG the assembly together on the bench. This would look much better and centre the push bolt over the hub for a straighter push. I'd also be happier about lending it out; it is the sort of thing that we should have available to forum members.